DENVER — Big crowds are expected in and around Denver to celebrate the Cinco de Mayo holiday this weekend and it will prompt road closures.

The city of Denver will host its annual family festival at Civic Center Park on Saturday and Sunday. Up to 400,000 people have attended in past years. The event will go from 10 a.m. to 8 p.m. Saturday and Sunday.

There will be road closures beginning Friday night surrounding the park, including Broadway; Colfax Avenue; Bannock, Cherokee and 15th streets; and Court Place.

Another Cinco de Mayo tradition has been the spontaneous cruising along Federal Boulevard that will result in severe disruptions.

The Denver Police Department has met with public and private groups and has created a traffic plan it believes will aid in safety, and relieve traffic congestion and noise in neighborhoods.

Denver Police say once there is significant congestion on Federal, east-west traffic will be restricted to crossing the boulevard at Kentucky, Mississippi, Alameda and West 10th avenues, and at major intersections north of West 20th Avenue.

In a release, Denver Police says the plan will have three phases:

Phase 1: Police will staff static posts on Federal and side streets will not be barricaded.

Phase 2: This will be implemented as the number of cruisers increases. Police will use barricades to restrict access to side street off Federal.

Phase 3: When normal traffic flow is prevented, some of the vehicles will be taken off from parts of Federal until the volume is normalized. Several diversion routes have been selected.

Once barricades are in place, only residents will be allowed in neighborhoods.

Denver Police say there will be strict enforcement of violations that pose a safety risk. It will also enforce traffic and sound ordinances that include excessive noise from stereos and horn honking.

Also, those younger than 18 will be subject to the city’s juvenile curfew ordinance that begins at midnight Friday and Saturday, and 11 p.m. Sunday.